/Engine/Source/Runtime/Core/Public/Math/Quat.h
Spherical interpolation. Will correct alignment. Result is normalized.
static [TQuat](API\Runtime\Core\Math\TQuat)< T > Slerp ( const [TQuat](API\Runtime\Core\Math\TQuat)< T > & Quat1, const [TQuat](API\Runtime\Core\Math\TQuat)< T > & Quat2, T Slerp )